Drilling and coring apparatus



lJun@ 1s, 1940. J F. CHAPPELL, 2,204,844

DRILLING AND CORING APPARATUS wmwwm June 18, 1940. J, F. CHAPPELL v 2,204,844

DRILLING AND CORING APPARATUS Filed Dc. 5, 19:58 5 sheets-sheet 2 v 7" '1 ff@ 1v T9 SMQ/1m@ g dames /T Cha/J/Jd/ June 18, 1940. J. F. CHAPPELL DRILLING AND CORING APPARATUS Filed Dec. 5, 195e 5 sheets-sheet 5 June 18, 1940. J. F. CHAPPELL DRILLING AND CORING APPARATUS Filed Dec. 5, 1938 5 Sheets-Shea?I 4 June 18, 1940. J. F. cHAPPELl.

DRILLING AND CORING APPARATUS y Filed Dec. 5, 1938 5 sheets-sheets me/nico@ dames f Cha/o/Jel/ www June 14, 1933.

Patented June 18, 1940- I I,

uNiTEn STATES PATENr voserei?.

DRILLING AND CORING APPARATUS James F. Chappell, Mineola, Tex.

Application December 5, 1938, Serial No. 244,002 Claims. (Cl. 2155-72) This invention relates to new and useful im- Figure 3 is a continuation of the par-ts shown provements in drilling and coring apparatus. in Figure 2 and illustrating the lower portion of This applicatin is filed as an improvement on said apparatus, A my prior Letters Patent No. 2,120,240, issued Figure 4.is an enlarged transverse, vertical,

sectional view taken through the upper portion 6 One object of the invention is to provide an of the device, improved apparatus which is particularly adapted Figure 5 is a continuation of the parts shown for use in drilling through hard formations and in Figure 4 and illustrating the lower portion of which is so constructed that cores may be readily the device,

l0 taken in such hard formations. Figure 6 is a horizontal, cross-sectional view, 1.0

An important object of the invention is to protaken on the line 6--8 of Figure 4, vide an apparatus for drilling wells which in- Figure '1 is a horizontal, cross-sectional view,

cludes an outer rotatable drill bit, and an inner taken on the line i--l of Figure 4, pilot or guide bit which'extends below the `outer Figure 8 is a horizontal, cross-sectional view, i6 bit, with improved means for imparting a taken on the line 8-8 of Figure 4, l5 hammering or reciprocating action to said inner Figure 9 is a horizontal, cross-sectional view, bit, whereby drilling through hard formations is taken on the line 9-9 of Figure 4,

facilitated, Figure 10 is a horizontal, cross-sectional view,

A particular object of the invention is to protaken on the line Ill-i0 of Figure 5,

vide an improved drilling or coring apparatus oi Figure ll is a horizontal, cross-sectional view, 20

the character described, wherein the inner bit taken on the line iI--H of Figure 5, element is readily insertable within and remov= Figure 12 1S a 1101120111781. CTOSS-Sciionul View,

able from the outer bit; said inner bit element taken on the line i2-|2 of Figure 5, being either a solid cutting bit and acting as a Figure 13 is a transverse, vertical, sectional pilot or guide bit during the drilling operation or view taken through the coupling element of the 25 being a tubular core bit, whereby a core may beA inner drill bit and. showing the same removed taken if desired. from the drill stem,

Still another object of the invention is to pro- Figure 14 is a partial isometric view of the vide an improved apparatus for drilling, and corfollower ring, D :m ing wells vwhich includes a drill stem having an Figure 15 is a partial isometric view of the 30 outer bit secured to its lower end and having an upper ratchet collar, improved spring actuated, reciprocating means Figure 16 is a partial isometric view of the therein, which means is reciprocated when the lower ratchet collar, stem is rotated, together with a removable inner Figure 17 is a partial isometric view of the 3.', bit adapted to be lowered through the drill stem elongate sleeve which receives the ratchet ele- 35 and connected with the4 reciprocating means, ment, whereby the inner bit is reciprocated as the outerl Figure 18 'is a partial isometric view of the bit is rotated; the construction of the stem and drill collar which is interposed between the lower associate parts being such that drilling fluid end of the drill stem and the outer drill bit, 4o may be conducted to and circulated through and Figure 19 is an enlarged transverse, vertical, 40 around said bits. sectional view taken through the core bit,

A construction designed to carry out the in-v Figure 20 is a view partly in section and partly vention will be hereinafter described, 'together in elevation showing a modied form of the inwith other features of the invention. vention, whereby the lnner'bit may be rotated 4.- The invention will be more readily understood with the outer bit, and 45 from a reading of the following specication and Figure 21 is a continuation of Figure 20, showby reference to the accompanying drawings, in ing the lower end of this arrangement. which an example of the invention is shown, and In the drawings, the numeral I0 designates a wherein: tubular drill pipe which has its upper end conm Figure lis an elevation of a drilling and'cor'ing nected to the usual square kelly or other drive 50 apparatus, constructed in accordance with the member (not shown), whereby said pipe maybe invention, rotated. The pipe extends downwardly within Figure 2 is a view, partly in elevation and the wellbore and has its lower end connected by partly in section, of the upper portion of said means of a coupling lcollar Il with an elongate apparatus, I. coupling member I2, which member has a bore 55 l2 of substantially the sarne diameter as the bore ld' of the drill pipe. The lower end or portion of the member l2 is enlarged so as to form an external, annular shoulder i3 and that portion of the member below said shoulder is ei;- ternally screw-threaded at if, whereby the upper end of an elongate sleeve may be connected thereto. The lower end of the sleeve is internally7 screw-threaded to receive the upper end of a tubular guide member or sleeve i@ and the lower end o this guide sleeve has a drill collar il' threaded thereinto (Figure 3). An outer drill bit i8 of any suitable construction is connected to the drill collar il and, with this arrangement, it-will be seen that when the drill pipe iti is rotated, a rotation is imparted to the drill bit il through the medium of the coupling element i2, sleeves l5 and i6 and the drill collar il. An

Xlal opening i9 is formed in the drill bit l@ l and an inner or pilot bit 2C, which is insertable through the vdrill stem ill, is arranged to project or extend through this opening. The lower end of the pilot bit Ztl is in a plane below the blades i8' of the outer bit i@ and, as will be explained, the inner bit is so connected to the drill stem that when said drill stem is rotated to rotate the outer bit i8, a hammering or reciprocating action is imparted to the inner bit.

The bottom drill collar l'i is clearly shown in Figures 3 to 5 and 18 and this collar is provided with an axial bore 2t extending entirely therethrough. Connecting nipples Il' are formed at each end of the collar and are externally screwthreaded so as to be connected with the guide sleeve i@ and the drlllbit it respectively. The wall of the bore 2li of the drill collar is formed with 'vertical recesses or channels 2i, which recesses extend between the nipples il" (Figure 18). Each nipple is formed with a plurality of vertical ports 22, which ports have their inner ends communicating with the recesses or channels 25. The outer ends of the ports in the lower nipple communicate with the interior of the drill bit body, while the outer ends of the ports 22 in the upper nipple communicate with the bore i6' of the guide sleeve l0. With this arrangement, fluid from the bore of the sleeve it may iiow downwardly through the ports 22 and the ver-a tical channelsor recesses 2l, then through the ports in the lower nipple Ell' and into the interior f the body of the drill bit i8. From the body, this uid flows through inclined ports 28 formed in the bit body adjacent the bit blades U8', whereby the fluid escaping through the ports 2S serves to lubricate and cool the blades i8', as well as to wash the cuttings removed during rotation of the hit.

The bore i' of the guide sleeve i8 is larger in diameter than the bore EE of the drill collar Il (Figure 3). Elongate guide ribs 2Q extend outwardly from the wall of the bore i6' of said sleeve and the vertical faces of said ribs terminate in vertical alinement with the bore 2Q' of the drill collar, whereby the distance between the diametrically opposite ribs 2K3 is substantially equal to the diameter of the bore 2Q', as is clearly shown in Figure 8. The ribs 2G terminate short of the upper and lower ends of the guide sleeve it and manifestly, fluid may flow through the sleeve iS between the guide ribs thereof.

The bore l5 of the elongate sleeve iii is of a larger diameter than the bore it' of the guide sleeve (Figures 2 and e). The wall of the bore i5' is recessed so as to forma plurality of vertical ribs 2B, four of which have been shown. As is acogerse clearly shown in Figures i? and 17,' the ribs are located diametrically opposite each other and the space between said ribs provides a liow channel for the fluid flowing through the sleeve l5, as will be explained. A pair ol diametrlcally opposed lugs 26 are formed on two o the ribs being located nearer the upper ends oi said ribs. These lugs are for the purpose or' irnpintu ing the reciprocating action to the inner hit 2-, as will be explained. rI'he lugsl 2G are adapted to engage and ride within vertical grooves 2l which are formed in the outer surface of an upper ratchet collar 2G (Figure 4). The grooves 2? are located diametrically opposite each other in the exterior surface of the collar. The lower edge portion of said collar is formed with plurality of ratchet teeth 2Q, which teeth are adapted to engage the teeth 38 formed on the upper end of a lower ratchet collar 3. The

collar 28 is formed with a vertical bore 28', while the collar 3i is formed with a similar bore and the diameter of said bores is substantially equal. For holding the ratchet collars 2t and 3l in engagement with each other, whereby the ratchet teeth 29 and 3l) contact each other, e coiled spring 32 has its lower end engaging the upper edge ofthe collar 2G (Figure 4). A follower ring 3S rests on the ripper end of the spring 32 and said ring is conned between the spring and the lower edge of the coupling member l2. The spring exerts ,its tension to con-- stantly urge the ratchet collar 28 downwardly' into engagement with the collar 8l. It is pointed out that the follower ring 33 is formed with an emernal, annular groove 36 and inclined ports extend through the ring and communicate with the groove. With such arrangement. fluid owing downwardly through the drill pipe i@ and the member i2 may ow downwardly through the ports 3S and enter the recesses between the ribs 2li within the sleeve i5. From the bore i5' of the sleeve I l, the fluid may enter the guide sleeve i@ and then flow downwardly through the drill collar il and drill bit body it, as has been explained.

Normally, the lower end of the lower ratchet collar Si rests on the upper edge oi the guide sleeve GES and to permit a flow of fluid from the sleeve #E to the sleeve i6 when the member 3f is seated on said sleeve, the ratchet collar is fori-ned with an external, annular groove 3G and inclined ports 3l lead from the groove to the bore of the collar El l. The provision ofthe groove 3G and ports lll permits a ow of uif from the sleeve ill to the guide sleeve i@ when the collar 3i is seated on the upper end of the guide sleeve.

From the above. it will be seen that when the drill pipe iti is rotated, a rotation ls imparted to the outer drill bit I8, whereby the cutting blades i6 thereof may perform the drilling operation. Rotation of the drill pipe lil will impart a rotation to the coupling member l2 and the sleeve i6, since said sleeve and said member are directly connected to the drill pipe. As the sleeve ill rotates, a rotation is imparted to the upper ratchet collar 28 due to the connection between said sleeve and said collar formed by' the engagement of the lugs 2S in the vertical grooves 2l of said collar. if the lower ratchet collar 8l is held stationary against rotation, it will be manifest that as the upper collar is rotated, the engagement of the ratchet teeth 29 and t@ riding over each other, will impart a hammering or reciprocating action to the lower collar Si. This vertical reciprocation of the collar 3| occurs within the sleeve I5 between the teeth 29 of the upper collar 28 andthe upper edge of the guide sleeve I3. Therefore-as thel equal to the diameter of the axial opening I3 in` the outer drill bit I8 (Figure 5). The upper end of the stem 38 lis secured to a tubular mandrel 39 which has an outer diameter greater than the outer diameter of said stem. It is pointed out that the diameter of the mandrel is greater than the diameter of the bore of the lowex` nipple I1' on the drill collar I1, whereby said mandrel cannot pass through this nipple. The stem 3l, however, has a diameter suiilciently small to pass through this lower nipple of the collar I1 and, therefore, when the lower end of the mandrel 33 strikes the nipple I'I', further downward movement of the inner bit 20 is prevented.

For connecting the tubular mandrel 33, which carries the inner bit 20, to the lower ratchet collar 3|, a coupling member A is connected to the upper end of said mandrel and this coupling element is insertable within the bore 28' of the upper ratchet collar 28 and also within the bore 3| of the lower ratchet collar 3|. 'I'he lower end of the bore 3|' of the collar 3|V is formed with an internal, annular shoulder 43 which ls located immediately above the inclined ports 31. As

yclearly shown in Figure 16, the shoulder 40 is bevelled and a plurality of notches 4I extend upwardly from said shoulder, the notches being formed in the wall of the bore 3|'. Although four notches havebeen shown, it is to be understood that any desired number may be provided anzthe top of each notch is bevelled as shown a The coupling member A, which is arranged to be connected with the ratchet collar 3|, is constructed in two sections B and C. 'l'.h'e lower section B comprises a cylindrical, bored body 43 which has an externally screw-threaded nipple 44, whereby the body may be connected withthe v mandrel 39. The axial borel 45 of the body exf tends vertically therethrough.l The upper endof this bore is internally screw-threaded at 48 so as to receive the lower threaded' end of a vtubular shank 41, which shank extends upwardly through an axial bore 43 of the upper member C of said coupling. The upper end of the bore 48. of the member C is enlarged as shown at 49 and the. shank is formed with an annular head 50 which is slidable vertically within vthe enlarged portion 49 of this bore.

With -this arrangement, it will be seen that the lower member or section B of the coupling mem- A is rigidly fastened to the upper end of the manl drel 39. The upper section C of said coupling member is slidable on the tubular shank 41, which is rigidly connected to the lower section B and, therefore, the upper section is movable a limited distance with relation to the lower section.

The lower end of `the upper section. C- is provided with a plurality of vertical grooves y6I which receive the upper ends of elongate vertical dogs 52., which upper ends are p ivoted end of said collar.

shoulder 59 (Figure 4) It is obvious that when the upper section is moved with relation to the lower section, with the rear faces of the dogs 52 riding on the curved faces of the slots 51|y in the lower section B, said dogs will be expanded or retracted, depending upon which way `the upper section C is moved. In other words, if the lower Iends of the dogs engage the upper ends of the slots 54 in the lower section B, said dogs will bey retracted so that their outer edges do not extend ybeyond the outer periphery of the lower section B. However, if the upper section C is lowered with relation to said lower section, the rear faces of the dogs 52 riding on the curved faces of the slots 54, will be expanded.

The lower end of each dog is formed with an outwardly extending lug 55 and the upper edge of this lug is inclined so as to be complementary to the upper bevelled surface 42 of the notches 5I in the ratchet collar 3|. When the coupling member A is lowered through the drill pipe I0,

coupling member I2 and into the sleeve I5 so as to pass through the bore 28' .of the upper ratchet collar and into the bore 3| of the lower ratchet lcollar 3|, the downward movement of said member A may continue until the lower edge of the mandrel 39 strikes the nipple I1' of the lower end of the drill collar I1. The length of the mandrel 39 is such that when its lower edge is resting on said nipple, the dogs 52 have their lugs 55 located below the lower end of the ratchet ,collar 3|.'- The coupling element is thenraised to expand the dogs 52, as will be presently ex-' plained, so that the lugs 55 of said dogs may enter the' notches 4| in the collar 3|, whereby "the coupling element is connected .to said collar. When the lugs 55^are engaged in the notches 4|, it'will be seen that the mandrel 39 which carries the inner bit 20 is connected to the lower ratchet collar 3I-and when the upper ratchet collar 28 is rotated to impart a reciprocating motion to the collar 3|, the mandrel 39 is also reciprocated. Since the inner bit 20 is carried by the mandrel 39, such reciprocation will impart a vertical reciprocating movement or hammering action to the inner bit 20.

In the operation of the apparatus, the outer. drill bit |8.is connected to the coupling collar I'I I6 is connected to the upper 'I'he sleeve I5 and coupling element I2 are also connected to the lower end of the drill pipe I0, as has been explained. At this time, the ratchet collars-28 and 3|', together with the spring 32 and follower ring 33, arelocated within the elongate sleeve l5. This assembly is lowered through the well -bore to a point nea-r the bottom of the hole. f

After the drill pipe has been positioned within the bore, 4the inner bit 28 which is carried by the mandrel 39 and which has the coupling mem-v ber A secured to its upper end is. lowered within and the guide sleeve the drill pipe. This lowering operation may be tinued until the lower end of the mandrel strikes the upper end of the nipple I1' which is formed at the lower end of the drill collar il and, at this time, the inner bit is projecting from the axial opening it in the outer bit i8.

Since the tool by which the mandrel 39 is lowered is secured to the upper section C of the coupling member A, this upper section C will be separated as far as possible from the lower section B. This is true because the weight of the mandrel and the bit 2G, which are secured to the lower section B of the coupling A, will pull the shank 4l downwardly until the head 58 of said shank rests on the shoulder 50' formed between the bore ,48 and the enlarged portion de of said bore of the upper section C. Thus, it will be seen that the lower section B which carries the mandrel 39 is suspended from the upper section C during the lowering operation and, at

j this time, the lugs 55 formed on the lower ends of the dogs 52, which are carried by the upper section C, are located at the upper end of the slots 54 in the lower section B, whereby said lugs are in their retracted position which permits them to clear the bores of the ratchet collars 28 and 3|. Therefore, so long as the lowering operation of thev inner bit and the mandrel 38, together with the coupling A at the upper end thereof, continues the dogs are in their retracted position.

The length of the mandrel 3S is such that when its lower edge strikes the lower nipple |'l' of the drill collar il to prevent further downward movey ment of the inner bit assembly, the lugs 55 of the dogs 52 have moved downwardly beyond the lower end of the lower ratchet collar 3|. The lowering tool met shown) is then released from the shoulder Tfi ef the upper element C of the coupling A, whereby said element may move downwardly with relation to the lower section B. As this occurs, the dogs 52 engaging the curved faces of the slots 5t are moved to ari-expanded position, whereby the lugs 55 o said dogs move outwardly in a radial direction.

To establish the connection between the ratchet collar 3| and the coupling member A, it is only necessary to lower the drill pipe until the inner bit 20 strikes the bottom oi the hole. when this occurs, a continued lowering of the drill pipe will cause the pipe and the sleeve l5 carried thereby to move downwardly, whereby the ratchet collar 3| moves downwardly with relation to the dogs 52 which are, oi course, held stationary due to the fact that the inner bit 2G is resting on the bottom of the hole. As the ratchet collar 3| moves downwardly with relation to the dogs,

the bevelled shoulder ill within the lower end of` said collar will strike the upper surface of the lugs 55 of said dogs and, by rotating the drill pipe and theA sleeve I5, a rotation is imparted to the ratchet collars d@ and 3|, whereby the notches lli may be registered with the lugs 55. As soon as such registration occurs, continued downward movement of the collar 3| causes the dogs to enter the notches l, as is clearly shown in Figure 4.

After the dogs have engaged in the notches M, a connection between the mandrel 3 which carries the inner bit 2l), and the lower ratchet collar 3|, is established. Rotation of the drill pipe Ill will impart a direct rotation to the outer drill bit 8, whereby the drilling operation will be performed. At the same time, the drill .pipe lo will rotate the sleeve I5 and said sleeve will rotate the upper ratchet collar 28 through the medium of the lugs 26 and the grooves 21. The

lower ratchet collar 3| is directly connected to lin Figure 19, for the bit 20.

the mandrel 39 through the dogs 52 and, since said mandrel is attached to the inner bit, said inner bit engaging the formation will prevent a rotation of the mandrel 39 and the collar 3|. Therefore, as the upper ratchet collar 28 is rotated and the lower ratchet collar 3| is held stationary, it will be manifest that the engagement of the ratchet teeth 29 and 3D will cause the lower ratchet collar to be reciprocated or moved vertically within the sleeve I5. This reciprocating movement of the ratchet collar 3| will be transferred to the mandrel 39 and to the inner bit 20. Thus, it will be seen that as the outer bit i8 rotates, the inner bit 20 is reciprocated.

Water, or other drilling uid, is pumped downwardly through the drill pipe and is supplied to the inner bit by passing through the tubular shank 47, then downwardly through the tubular mandrel 3S and outwardly through ports |20 provided for this purpose in the bit 20. In passing to the outer bit I8, the water passes downwardly around the coupling A and ratchet collars 28 and 3| through the vertical recesses formed in the wall of the bore I5 of the sleeve l5. This water then flows downwardly through the guide sleeve |6 and through the ports 22 in the drill collar and :finally escapes through the outlets 23 provided in the bit body |8. As has been explained, the ports 23 are located adjacent the cutting blades I8 of the outer bit..

When it is desired to remove the inner bit 20 for any purpose whatever, it is only necessary to lower a suitable tool (not shown) which may be engaged beneath the shouder 56 at the upper end of the coupling member A. When this is done, the drill pipe l0 is then raised a slight distance so as to relieve the lugs 55 of the dogs 52 of the weight imposed thereon. This causes the lugs to move downwardly within the slots 4| and an upward pull on the upper section C oi' the coupling member will immediately cause the dogs to be retracted along the inner curved surface of each slot 5d. As soon as the dogs are retracted, the coupling member A may be readily removed and the mandrel .'39 with the bit 2t at its lower end raised upwardly through the drill pipe. The bit 2d, which has heretofore been described, is adaptable when drilling through hard formations as it provides a pilot or guide bit to lead the large or outer bit iii through the formation. However, if it is desired to take a core, it is only necessary to substitute a core bit 26a as shown nected to the lower end of the mandrel 39 and is provided with an axial bore 2Gb and as the hammering action is imparted to said core blt the core will travel upwardly into the bore of said bit. To retain the core within said bore, the usual spring finger 2Go may be provided. To .prevent downward circulation of the drilling iluid through the mandrel 39 and the core bit 2da, a ball (not shown) may be dropped through the drill pipe lo so as to engage and close the upper end of the head 5U of the shank tl, whereby the bore of the mandrel is closed.

In many instances, it might be desirable to rotate the inner bit 2G with the outer bit I8, in which event the inner bit must be directly connected with the drill so as4 to rotate therewith. ,f

i6 and this unit includes an elongate sleeve 6| 75 which is constructed in a manner similar to the sleeve l5, with the exception that it is shorter in length. The

with vertical ribs 62, similar to the ribs 25 of the sleeve |5, and also has diametrically opposed lugs 63 therein. The lugs are arranged to engage within vertical grooves 64 which are formed in the exterior surface of a coupling collar 65. The lower end of the collar normally rests on the upper end of the'sleeve |6, being held in such position by a coiled spring 66 which has its lower end engaging the upper end of the collar. The upper end oi the spring contacts a follower ring 46l, which, in turn, engages an internal annular shoulder 68 formed within the bore of the sleeve 6|.

The bore 65 of the collar 65 is of substantially i the same size asv the bores 28' and A3| of the .ratchet collars 28 and 3| respectively, and its lower end isconstructed in a manner similar to the lower end of the lower ratchet collar 3|. As shown in Figure 20, the bore 65' has an internal annular shoulder 69, similar to the shoulciprocates -4 coupling element A,

-of being opposite the ratchet collar 3|,

' posing the unit so in the drin pipe,

rotated, asdesired, by i der 40 of the collar 3|, and a plurality of notches 10, similar to the notches 6| of said collar 3|. The top of the notches 'l0 Below the internal shoulder 69', the lower end of the collar 65 is slotted at 12, such slots being pro@ vided in place of the groove 36 and openings 31 in the collar 3| to permit by-pass of drilling fluid. It is noted that if desired, the collar 3| could also be formed with the slots or, if desired, the collar 65 could have the openings 31.

Since the collar 65 is connected directly to the drill stem through the lugs 63, it is manifest that said collar will be rotated therewith at all times. When the inner bit 20 is connected with the ratchet collars 28and 3| by means of the stem 36 and as has been described, the stem extends through the bore 65 of the collar 65 and no connection is set up between the stem 39 and said collar 65, whereby the inner bit retime, the collar 65 is not functioning, being rotated with the drill stem.

when it is desired te rotate the inner bit 2c,

f it is only necessary to remove the inner bit from the drill pipe, as has been explained, and replace the stem 39 with a stem 39' of a shorter'length, whereby when the inner bit is again lowered through the drill pipe, the coupling A, instead is disposed opposite the collar 65. 'Ihe dogs 52 of the coupling element are then engaged with the notches 1li of the collar 65 and aconnection is made `between the stem 39' and said collar. Since the collar 6511s constructedin the same manner as the ratchet collar 3|, this connection is established in the same manner as hereinbefore described. After such connection, a rotation of thef drill pipe will impart rotation to the inner bit 20. Thus. it will be seen that by interthe inner bit may be reciprocated or mere changing-the length ofthe stem .whieh carries said inner bit.- n

The foregoing ldescription oi the invention is explanatory thereof and various changes in the size, 'shape and materials, as well as in the details of the illustrated construction may be made,

within the scope of the appended claims, without departing from the spirit oithe invention.

bore of the sleeve 6| is provided provide shoulders 1|.

with a hammering action'. At this Y I claim and desire to secure by Letters ior attaching the inner a rotatable drill pipe, means 'for rotating said pipe, a drill bit having an axial opening threaded onto the lower end of the drill pipe and rotatable therewith, a reciprocating element mounted within the drill pipe, 'an inner blt insertable through the drill pipe and adapted to extend below the outer bit, means for connecting the inner bit with the reciprocating element, and

, assembly insertable through the drill) pipe and element and having a bit at its lower end which projects through the opening in the outer bit, and means for attaching the inner bit assembly to the reciprocating element, whereby a vertical reciprocating movement is imparted to the inner` bit when the drill pipe is rotated to rotate the outer bit.

3. A drilling and coring apparatus including, a rotatable drill pipe, means for rotating said pipe, a drill bit having an axial opening threaded onto the lower end of the drill Ipipe and rotatable` therewith, an annular reciprocatingv element within the drill pipe, means for connecting said element with the drill pipeso as to reciprocate the same when the pipe is rotated, an inner bit -assembly insertable through the drill pipe and element and having a bit at its lower end which proiects through the opening in the outer bit,

ancilmeans i'or removably connecting the inner bit assembly to the reciprocating element, whereby a vertical reciprocating movement is imparted to the inner bit whengthe drill pipe'is rotated to rotate the outer bit.

4. A drilling and coring apparatus including, a rotatable drill pipe, means for rotating said pipe, a drill bit having an axial opening threaded onto the lower end oi' the drill pipe and rotatable -therewith. an annular reciprocating element.

within the drill pipe, means for connecting said element with the drill pipe so as to reciprocate fthe same when the pipe is rotated, an inner bit assembly adapted to be run into the drill pipe and through thevv reciprocating element on a exible line and having a bit at its lower -end which projects through the outer bit so as to be in a plane therebelow. land a coupling on the upper end oi the inner bit assembly arranged to `engage the reciprocating element to connect said element to the assembly, whereby the inner bit is reciprocated vertically when the drill pipe is rotated to rotate the outer bit. v

l5. A drilling and coring apparatus includingfa vroti'itable drill pipe, means for rotating said pipe, a drill bit having an axial opening threaded onto the lower end o! the `drill pipe and rotatable therewith, anannular reciprocating elementwithin the drill pipe, means for connecting said ele-I ment with the drill pipe so as to reciprocate the same when the pipe is rotated, an -inner bit assembly insertable through the drill pipe and element and'having a bitat its lower end which projects through the .opening in .the outer jbit, means bit assembly to'tlie reciprocating element, whereby a' vertical reap- 75 rocating movement is imparted to the inner bit when the drill pipe is rotated to rotate the outer bit, and means for delivering a drill fluid from the drill pipe to both the inner and outer bits.

6. A drilling and coring apparatus including, a rotatable drill pipe, means for rotating said pipe, a drill bit having an axial opening attached to the lower end of the drill pipe and rotatable therewith, an annular reciprocating element within the drill pipe, means for connecting said element with the drill pipe so as to reciprocate the same when the pipe is rotated, an inner bit assembly adapted to be run into the drill pipe and through the reciprocating element on a exible line and having a bit at its lower end which projects through the outer bit so as to be in a plane therebelow, a coupling on the upper end of the inner bit assembly cating element to connect said element to the iluid from the outer bits.

7. A drilling and coring apparatus including, a rotatable drill pipe, means for rotating said pipe, an outer drill bit having an axial opening secured to the lower end of the drill pipe and rotatable therewith, a reciprocating collar conned within the drill pipe, a rotatable collar above the reciprocating collar and engaging the same,'means for connecting the rotatable collar with the drill reciprocating bit is reciprocated vertically when the drill pipe is rotated to rotate the outer bit.

8. A drilling and coring apparatus including, a rotatable drill pipe, means for rotating said pipe, an outer drill bit having an axial opening secured to the lower end of the drill pipe and rotatable therewith, a reciprocating collar confined within the drill pipe, a rotatable collar above the reciprocating collar and for connecting the rotatable collar with the drill a rotatable drill pipe, means for rotating said pipe, a drill bit having an axial opening attached to the lower end of the drill pipe and rotatable therewith, a reciprocating element mounted within the drill pipe, an inner bit assembly insertable through the drill pipe and including a tubular core bit which projects below the outer bit, means for connecting the bit assembly with the reciprocating element, andmeans for imparting a reciprocating Amotion to the inner bit assembly when the drill pipe is rotated, whereby the core bit is reciprocated when the outer 10. A drilling and coring apparatus including, a rotatable drill pipe, means for rotating said pipe,

arranged to engage the reciprowhereby rotation of one engaging the same, means' bit is rotated.`

a drill bit having an axial opening attached to the lower end of the drill pipe and rotatable therewith, an annular reciprocating element within the drill pipe, means for connecting said element with the drill pipe so as to reciprocate the same when the pipe is rotated, an inner blt assembly insertable through the drill pipe and element and having a tubular'core bit at its lower end which projects through the opening in the outer bit, and means for attaching the inner bit assembly to the reciprocating element, whereby a vertical reciprocating movement is imparted to the inner tubular core bit when the drill pipe is rotated to rotate the outer bit.

l1. A drilling and coring apparatus including, a rotatable drillpipe, means for rotating said pipe, a drill bit having an axial opening attached to the lower end of the drill pipe and rotatable therewith, an annular reciprocating element within the drill pipe, means for connecting said element with the drill pipe so as to reciprocate the same when the pipe is rotated, an inner bit assembly insertable through the drill pipe and element and having a tubular core bit at its lower end which projects through the opening in the outer bit, and means for removably connecting the inner bit assembly to the reciprocating element, whereby a vertical reciprocating movement is imparted to the inner tubular core bit when the drill pipe is rotated to rotate the outer bit.

12. A drilling and coring apparatusincluding, a rotatable drill pipe, means for rotating said pipe, an outer drill bit having an axial opening secured to the lower end of the drill pipe and rotatable therewith, a rotatable collar within the drill pipe and connected therewith so as to be rotated thereby, a collar confined within the drill stem adjacent the rotatable collar and capable of a limited axial movement therein, the collars having ratchet teeth on their contiguous edges which are in engagement with each other, collar imparts a vertical reciprocating movement to the other collar, an inner bit assembly insertable through the drill stem and collars and including an inner bit which extends through the opening in the outer bit, and means for connecting said assembly to the reciprocating collar, whereby a hammering action is imparted to the inner bit when the drill pipe is rotated to rotate the outer bit.

13. A drilling and coring apparatus including, a rotatable drill pipe, means for rotating said pipe, an outer drill bit having an axial opening secured to the lower end of the drill pipe and rotatable therewith, a rotatable collar within the drill pipe and connected therewith so asl to be rotated thereby, a collar confined within the drill stem adjacent the rotatable collar and capable of a limited axial movement therein, the collars having ratchet teeth on their contiguous edges which are in engagement with each other, whereby rotation of one collar imparts a vertical reciprocating movement to the other collar, an inner bit assembly insertable through the drill stem and collars and including an inner bit which extends through the opening in the outer bit, and a coupling for detachably connecting the inner bit with the reciprocating' collar, whereby said inner bit is reciprocated when the drill pipe is rotated to rotate the outer bit.

14. A drilling and coring apparatus including, a rotatable drill pipe, means for rotating said pipe, a drill bit having an axial opening attaehed to the lower end of the drill pipe and rotatable therewith, an annular reciprocating element within the drill pipe, means for connecting said element with the drill pipe so as to reciprocate the same when the pipe isrOtated, a rotatable element within the drill pipe and rotatable therewith, an inner bit assembly insertable through the drill pipe and having a bit at its lower end which projects through the opening in the outer bit, and means carried by the inner bit assembly arranged to be connected with the reciprocating element or with the rotatable element, whereby the inner bit may be reciprocating or rotated by the rotation of the drill pipe and outer drill bit.

15.l A drilling and coring apparatus including, A

a rotatable drill pipe, means for rotating said pipe. a drill bit having an axial opening attached to the lower end of the drill pipe and rotatable therewith. an annular reciprocating element within the drill pipe, means for connecting said elementwith the drill pipe so as to reciprocate the same when the pipe is rotated, a rotatable element within the drill pipe and rotatable therewith, an. inner bit assembly adapted to be run through the drill pipe on a ilexible line and having a bit at its lower end which projects through the outer bit so as to be in 'a plane therebelow, and a coupling on the upper end of the inner bit assembly arranged to be removably connected with either the. reciprocating element or the rotatable element, whereby the inner bit maybe reciprocated or rotated. by the rotation of the drill pipe and outer drill bit.

JAMES F. ,CHAPPELL 

